Hey Tyler,

I have had really hit and miss experiences with the Sigma lenses that I have purchased. The 15-30 F3.5-F4.5 was probably the best wide angle lens that I ever owned, at least in terms of sharpness - even better than my Canon 16-35 wide open. I got rid of it because the focus mechanism was really slow.

I owned the 28-70 F2.8 Sigma and I had to get 3 copies before I got a good one. I wound up dumping it for the 28-135 IS, which while being slower (lens wise) still had a significantly faster focus engine on it. I then went to the 28-70 F2.8 Canon lens, which I own to this day (I purchased it about 3 weeks before the 24-70 was announced, LOL).

I still own a 15 F2.8 fish eye that I use for certain things, but it is usually collecting dust (I did break it out during a pet portrait last month, but that was the first time in a while). I think it is a good lens - certainly for the money.

So the long and the short of it is that while I cannot comment on this particular lens, the specs look great. The fact that it is OS is really nice. However, my experience owning Sigma lenses has been hit and miss - though I believe generally better hits than misses.

If you pick one up and want to test it out, let me know.

James